Bovidae is the biological family of cloven-hoofed, ruminant mammals that includes cattle, bison, buffalo, antelopes, and goat-antelopes such as sheep and goats. There are 143 extant species and 300 known extinct species of bovids, which are divided into either 11 major subfamilies, or two subfamilies with 13 tribes. The earliest known bovid had evolved by 20 million years ago, in the early Miocene.
Source: Wikipedia
